A bacterial gene, fip, required for filamentous bacteriophage f1 assembly

Abstract

An E. coli mutant which does not support the growth of filamentous bacteriophage f1 allows phage f1 DNA synthesis and gene expression in mutant cells, but progeny particles are not assembled. The mutant cells have no other obvious phenotype. On the basis of experiments with phage containing nonlethal gene I mutations and with mutant f1 selected for the ability to grow on mutant bacteria, we propose an interaction between the morphogenetic function encoded by gene I of the phage and the bacterial function altered in this mutant. The bacterial mutation defines a new gene, fip (for filamentous phage production), located near 84.2 min on the E. coli chromosome.